A hollow spherical cerium dioxide nanomaterial, preparation method and application thereof; wherein the preparation method uses glucose as a carbon source, urea as a precipitant, cerium trichloride as a cerium source, and water as a solvent to prepare a cerium dioxide/carbon composite material by a hydrothermal method, and then, a hollow spherical cerium dioxide nanomaterial with a multi-shell layer structure is obtained by calcination in a muffle furnace. By adjusting the amount of urea and the calcination temperature, a number of shell layers of the material can be adjusted. Moreover, in the nanomaterial, the number of shell layers can be adjusted, large spacing exists between shell layers, specific surface area can be increased, wherein contact area of the material with an electrolyte increases, but also structural collapse caused by a volume expansion of an electrode material during charging and discharging can be alleviated, and the electrochemical performance is effectively improved.

A method for producing lithium hydroxide that allows reducing a load of removing divalent or more ions with an ion-exchange resin is provided. The method for producing lithium hydroxide includes steps (1) to (3) below. (1) a neutralization step: a step of adding an alkali to a first lithium chloride containing liquid to obtain a post-neutralization liquid, (2) an ion-exchange step: a step of bringing the post-neutralization liquid into contact with an ion-exchange resin to obtain a second lithium chloride containing liquid, and (3) a conversion step: a step of electrodialyzing the second lithium chloride containing liquid to obtain a lithium hydroxide containing liquid. Since this producing method allows roughly removing divalent or more ions in the neutralization step, a load of metal removal with the ion-exchange resin is reducible.

Disclosed is a method of manufacturing a secondary battery, the method including: manufacturing a pre-lithiation cell including a negative electrode and a lithium metal counter electrode and pre-lithiating the negative electrode by charging the pre-lithiation cell; separating the pre-lithiated negative electrode from the pre-lithiation cell and manufacturing an electrode assembly including the pre-lithiated negative electrode and a positive electrode; impregnating the electrode assembly with an electrolyte; activating the impregnated electrode assembly by performing a first charging the impregnated electrode assembly; removing gas generated in the activation; discharging the activated electrode assembly immediately after removing the gas; and performing a second charging on the discharged electrode assembly.

An estimation apparatus estimates an internal state of an energy storage device having a positive electrode, a negative electrode including a negative active material that contains SiO.sub.x, and a nonaqueous electrolyte, the energy storage device changing from a positive-electrode limiting type, in which a discharge capacity is limited by the positive electrode, to a negative-electrode limiting type, in which the discharge capacity is limited by the negative electrode. The estimation apparatus estimates the internal state of the energy storage device by using a voltage value and an energization amount in a predetermined voltage range of the energy storage device or at a predetermined measured voltage value, or based on information on the shape of a discharge curve of the energy storage device.

A method of manufacturing a negative electrode, which includes: applying a negative electrode slurry on a negative electrode current collector and subjecting the applied negative electrode slurry to a first roll-pressing to form a negative electrode active material layer; pre-lithiating the negative electrode active material layer to form a pre-lithiated negative electrode active material layer; and subjecting the pre-lithiated negative electrode active material layer to a second roll-pressing, wherein the negative electrode active material layer includes a silicon-based active material, and a ratio (p.sub.1/p.sub.2) of porosity (p.sub.1) of negative electrode active material layer after the first roll-pressing to porosity (p.sub.2) of negative electrode active material layer after the second roll-pressing is in a range of 1.05 to 1.65.

A packaging film including a protective layer, a first bonding layer, a metal layer. a second bonding layer and a sealing layer. The protective layer, the first bonding layer, the metal layer. the second bonding layer, and the sealing layer are sequentially stacked. The protective layer includes a polymer resin layer and a carbon material.

An electrochemical cell for a lithium accumulator comprising: a negative electrode comprising metallic lithium as active material; a positive electrode associated with an aluminium current collector; and an electrolyte placed between the negative electrode and the positive electrode, wherein the negative electrode is provided with a layer comprising a compound containing aluminium at its face in contact with the electrolyte, and in that the electrolyte comprises at least one lithium salt chosen from among lithium imide, lithium triflate, lithium perchlorate salts and mixtures thereof.

An electrolyte solution for a secondary battery according to an exemplary embodiment includes a lithium salt, a non-aqueous organic solvent, and a silatrane-based compound represented by Chemical Formula 1. By including the electrolyte solution for a secondary battery according to an exemplary embodiment, a secondary battery can exhibit improved storage characteristics and improved capacity characteristics.

A lithium-ion secondary battery containing: a positive electrode; a negative electrode; a separator between the positive electrode and the negative electrode; and an electrolyte, in which the negative electrode may contain silicon or a silicon compound, a binder, and a carbon nanotube, the binder may contain a compound having a structure in which a linear molecule penetrates a cyclic molecule, and the electrolyte may contain an electrolytic salt containing one or more elements selected from the group consisting of boron, carbon, nitrogen, oxygen, and sulfur.

A main object of the present disclosure is to provide a coated anode active material capable of preventing the reaction resistance from increasing during high cycles. The present disclosure achieves the object by providing a coated anode active material including: a Si-based active material; and a coating layer that coats at least a part of a surface of the Si-based active material and includes a lithium oxide; wherein a silicon oxide layer is formed between the Si-based active material and the coating layer.